.div_middle {
    width: 40%;
    height: 400px;
    border: 1px solid black;
    margin: 0 auto;
}
.div_input {
    width: 100%;
    height: 100px;
    border: 1px solid red;
    color: aliceblue;
}
.input_number {
    height: 100%;
    width: 100%;
    font-size: 2rem;
    background-color: rgb(93,92, 90);
}
.div_btnRow {
    width: 100%;
    height: 50px;
    border: 1px solid blue;
}
.button_1 {
    width: 100%;
    height: 50px;
    font-size: 2rem;
    font-weight: bold;
    color: white;
    background-color: rgb(93,92, 90);
}
.button_2 {
    width: 100%;
    height: 50px;
    font-size: 2rem;
    font-weight: bold;
    color: white;
    background-color: rgb(253,158,68);
}